Great find!
I'm from Detroit and the cheapest I can find is ~1400-1600 out of DTW.... buttttttt
If you take a $29 bus from Detroit to Toronto and then a cab over to YYZ, maybe $30 for an Uber you can get a $1030 Canadian Dollar ticket.
$1030*.75 = $772.50 USD.
On the way back, skip the leg from DTW -> YYZ.
20400 miles / 772 = 3.66cents / mile for the full trip.
Very tempting. I've already looked at what it would take to stay in Singapore for a day or two to explore before heading home. Looks like no Visa required for US Passport holders.